Adding external dependencies for projects

As a project manager, you can use an external dependency to set up a dependency from a task in one project to a task in another project.

External dependencies help you to see the impact of changes in project schedules when a predecessor project changes.

How external dependencies work

To define the external dependency, select a project task from the predecessor project to be linked to the task in the successor project. When an external dependency is added, the system adds shadow tasks in both the successor and predecessor projects.

A shadow task is a read-only task in the respective project. It has the database attribute shadow set to true and orig_sys_id pointing to the sys_id of its original task. The shadow task is kept in sync with its original task whenever the relations are processed.

In addition to the shadow tasks, two shadow relations are also added in the planned_task_rel_planned_task table. These relations are shadows of the original relations.

For example, for two projects, project P1 is the predecessor project, and P2 is the successor project. Project P1 has a task T1, and project P2 has a task T2.

If an external dependency is created from T1 to T2, the following tasks are added in the two projects:

After adding the external dependency, the following shadow relation records are created in the planned_task_rel_planned_task table:

Where:

• Parent is the predecessor project.
• Child is the successor project.
• Project is the project where the relation is seen.
• External is the external dependency.

Parent Topic:Using Project Management